866001 has 8 divisors (see below), whose sum is σ = 1215520. Its totient is φ = 546912.

The previous prime is 865993. The next prime is 866003. The reversal of 866001 is 100668.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 866001 - 2³ = 865993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7540 + ... + 7653.

It is an arithmetic number, because the mean of its divisors is an integer number (151940).

2⁸⁶⁶⁰⁰¹ is an apocalyptic number.

It is an amenable number.

866001 is a deficient number, since it is larger than the sum of its proper divisors (349519).

866001 is a wasteful number, since it uses less digits than its factorization.

866001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15215.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 866001 is about 930.5917472232. The cubic root of 866001 is about 95.3175339633.

Adding to 866001 its reverse (100668), we get a palindrome (966669).

The spelling of 866001 in words is "eight hundred sixty-six thousand, one".